Time system



July 25, 1944. G. c. ENGEL ETAL 2,354,511

TIME SYSTEM Filed March 11, 1942 2 Sheets-Sheet l IN V EN TORS GEO/P65 C, ENGEL ATTORNEY.-

July 25, 1944. I C ENGEL ETAL 2,354,511

TIME SYSTEM Filed March 11, 1942 2 Sheets-Sheet ,2

INVENTORS. GEORGE c ENGEL Y ADOLPH AMEND, J2.

- ATTORNEY.

Patented July 25, 1944 TIME SYSTEM George C. Engel, Ridgewood, and Adolph Amend,

Jr., Harrington Park, N. J., assignors to General Time Instruments Corporation, New York, N. Y., a corporation of Delaware Application March 11, 1942, Serial No. 434,210

6 Claims.

This invention relates in general to time systems and more particularly to such a system in which the clocks, time stamps, recorders and other secondary apparatus are driven by synchronous motors. The main object of the inven tion is to provide a synchronous motor time system which can be easily reset to correct time following current interruptionsand in which the entire system may be controlled from a central or control point.

According to one feature of the invention, each secondary apparatus incorporates a speed change mechanism so that the device may be driven at increased speed by the synchronous motor.

According to another feature of the invention, the speed change mechanism comprises a gear shifting arrangement controlled from a central or control point.

One of the main features of the invention relates to the control apparatus comprising means for automatically resetting the entire system to correct time following a current interruption.

particular feature of the control apparatus lies in the arrangement whereby the entire mechanism is at rest during normal operation of the system.

Another feature of the control apparatus is the provision of a spring driven clock movement which is positively started at the instant of current failure and is positively stopped at the instant when the system has been reset to correct time following the current interruption.

The above and other objects and features of the invention not specifically mentioned will best be understood from a perusal of the following specification when read in connection with the accompanying drawings, comprising Figs. 1 to 3, inclusive, in which:

Fig. 1 is a diagrammatic view of the automatic control apparatus with the elements shown in perspective;

Fig. 2 is a similar view of a secondary apparatus; and

Fig. 3 is a schematic circuit diagram of a system with a manual reset control.

Referring in general to the drawings, Fig. 1 discloses the master control apparatus comprising an eight day clock movement indicated generally by the reference character I. This clock movement consists of the three mounting plates 85, 85 and 81 separated by the spacing pillars 88 and mounting in suitable bearings the various shafts which in turn carry the necessary gear wheels and pinions indicated generally as 3. This clock movement includes the usual balance wheel 2. The shaft 4 extending from the clock movement is revolved at the rate of one revolution per hour and its outer end carries the crown cam 5 having the'laterally extended cam point 6. This shaft also carries the pinion l engaging gear wheel 8 which is mounted on a shaft together with the pinion 9. Pinion 9 engages gear wheel l0 fixedly mounted on shaft l I. The gearing, 1 to Ii] inclusive, reduces the speed in the ratio of twelve to one so that the shaft H is revolved at the rate of one revolution in twelve hours Shaft H at its other end carries the crown cam l2 which is similar to cam 5 and has the laterally extending cam point l3,

A self-starting synchronous motor is indicated at M and comprises coil 54 with the associated field structure and rotor I 5 mounted on shaft l6 which carries pinion I! at the outer end. Pinion l'l engages gear wheel l8 mounted on the same shaft as pinion l9 which in turn engages the gear wheel mounted on shaft 2|. This gearing is so designed that the shaft 21 revolves at the rate of three revolutions per hour. Shaft 2| in turn is geared to shaft 28 by a twelve to one reduction gearing through pinion 24, gear wheel 25, pinion 26 and gear wheel 21 so that shaft 28 makes one revolution every four hours. The shaft 2| carries at its end a crown cam 22 with cam point 23 normally engaging the cam point 6 of cam 5. Shaft 28 carries a similar cam 29 with cam point 30 normally engaging the cam point 13 of cam l2. The other end of shaft 2| bears against the contact bearing spring 3| and with the cams 5 and 22 in normal position holds the contacts 32 open. Similarly, shaft 28 bears against the contact carrying spring 33 and with cams I2 and 29 in normal position maintains contacts 34 in open position.

The control apparatus also includes a duplex relay 35 comprising coils 36 and 31 and their associated cores. The armature 38 is pivoted at its center on shaft 39 and is controlled by the two sections of the relay and a spring 90 biasing it against the core of coil 31. Armature 38 is also provided with a somewhat flexible arm or lever 40 having a laterally extending projection 4| which engages the balance wheel 2 of clock movement I when armature 38 is attracted to magnet 36.

A source of 110 volt alternating current is connected with the control apparatus at terminal 44 and 45 and the three wire circuit comprising conductors 51, 59 and 58 extends from terminals d6, 47. and 48 to the secondary apparatus.

A typical secondary apparatus is disclosed diagrammatically in Fig. 2 of the drawings. This comprises the self-starting synchronous motor with its coil 5| connected to conductors 51 and 59 of the secondary circuit, The rotor 62 is mounted on shaft 63 which also mounts the pinion 64 normally driving the clock hands 18 through suitable gearing including gear wheel 65, elongated pinion 66, gear wheel 51 mounted on the axially movable shaft 83 which also mounts the pinion 68, gear wheel 10 mounted on shaft 12 which at its other end carries the pinion 13, gear wheel 14, pinion 15 and gear wheel 16 mounted on the minute shaft 11. The standard twelve to one reduction gearing between shaft 11 and the sleeve bearing the hour hand has been omitted for the sake of simplifying the drawings. The secondary clock also includes an electromagnet 19 having coil 86 and armature 8|. The armature 8| carries a spring lever extension 82 adapted to engage the end of shaft 83. Shaft 83 is normally held in the position shown in the drawings by means of the spring 84 bearing against its other end. Shaft 83 also carries a second pinion 69 and shaft 12 carries a second gear wheel 1|, these two being normally out of engagement. When the magnet 19 is energized, the attraction of its armature axially moves shaft 83 to disengage pinion 68 from gear wheel 10 and to engage pinion 69 with gear wheel 1|. This changes the gear ratio between the synchronous motor 60 and the clock hands 18 so that the latter are now driven at three times normal speed.

Fig. 3 of the drawings schematically illustrates a resetting system with a manual control instead of the automatic control shown in Fig. 1. The control apparatus in this case consists of a clock C, which is in all respects similar to the clock as shown in Fig. 2, and a manually operable key R. A three wire circuit comprising conductors I66, |6| and I62 extends to the secondary system diagrammatically illustrated by the clocks S--| and S2 which are in all respects similar to that disclosed in Fig. 2.

With regard to the operation of the automatic resetting system disclosed in Figs, 1 and 2, it will be seen that magnet 36 is connected directly across the alternating current supply source by means of conductors 49 and 50. The armature 38 is, therefore, in such position that spring lever 4| is in contact with balance wheel 2 and maintains the clock movement I at rest. Furthermore, as long as the current supply source is uninterrupted the circuit to synchronous motor I4 is open at contacts 32 and 34. Alternating current is supplied to the secondary system from conductor 42, terminal 44 which is connected to terminal 41, conductor 59 of the secondary circuit, conductor 51 of the secondary circuit, terminals 46 and 45, and supply line 43. In normal operation, therefore, the secondary clocks are supplied with alternating current and are driven at normal speed by their respective synchronous motors.

When the current supply source is interrupted, magnet 36 is deenergized and armature 38 is pulled down against magnet 31 by means of spring 96. During this movement of the armature the spring lever 4i releases balance wheel 2 and at the same time sets it in motion so that the clock movement I is started. As soon as shaft 4 begins to revolve cam 5 is rotated in the direction indicated on the drawings so that the cam point 6 leaves the cam point 23 thereby permitting the spring lever 3| to move shaft 2| axially and allowing contacts 32 to close. This prepares the circuit to the coil 54 of synchronous motor l4 and to magnet 31, these two being connected in parallel. The clock movement I continues to operate to time the duration of the current interruption since, of course, the secondary clocks stopped as soon as the current was interrupted.

When current flow is resumed a circuit is completed from supply line 42, terminal 44, conductor 55, through coil 54 of secondary motor l4 and coil of magnet 31 in parallel, contacts 32 and 34 in parallel, conductor 5|, terminal 45 to supply line 43. At the same time the circuit to magnet 36 is closed from the terminals 44 and 45 through conductors 49 and 50. However, magnet 31 assisted by spring 96 maintains armature 38 in a position in contact with magnet 31. The synchronous motor is thus placed in operation and drives the shaft 2| in the direction indicated by the arrow at the rate of 3 revolutions per hour. Thus the cam point 23 will gradually overtake the cam point 6 and when this occurs contacts 32 will be opened to stop the resetting operation.

At the time the clock movement is started and contacts 32 are closed a circuit is completed from supply line 43, terminal 45, conductor 5|, contacts 32, conductor 56, terminal 48, secondary line 58, coil of all secondary clock magnets such as 19, secondary line 59, terminal 41, terminal 44, back to supply line 42. Magnet 19, therefore, energizes when current flow is resumed and moves shaft 83 axially to engage pinion 69 with gear wheel 1| and thereby drive the clock hands 18 at three times normal speed from synchronous motor 66. It will thus be seen that the clock hands of all secondary clocks and the cam 22 are driven at three times normal speed and that when the cam point 23 has overtaken cam point 6 and opened contacts 32, all secondary clocks will again be reset to correct time. When contacts 32 are opened the synchronous motor l4 immediately stops and the magnet 31 is also deenergized. Magnet 38 is powerful enough to overcome the tension of spring and armature 38 is, therefore, attracted to magnet 36 bringing the spring lever 4| into engagement with balance wheel 2 and stopping the clock movement.

The opening of contacts 32 also opens the circuit to the magnets 19 in the various secondary devices. Magnet 19 of each device releases and shifts shaft 83 axially by means of spring 84 to disengage pinion 69 from gear wheel 1| and to reengage pinion 68 with gear wheel 16. This restores the normal gear ratio of the train and the secondary clock hands are now driven at proper speed from the synchronous motor 66.

The system is now back to normal operation with the secondary clocks driven at normal speed by their synchronous motors and with the clock movement I and synchronous motor I4 in the control apparatus both at rest. Magnet 36 is normally maintained energized to keep armature 38 in the position shown in the drawings with spring lever 4| in engagement with balance wheel 2 of the spring driven movement.

It is, of course, obvious that this control apparatus will take care of current interruptions up to twelve hours duration since at the end of a one hour period contacts 34 will be maintained in closed position even though contacts 32 are temporarily opened during the time that cam point 6 and 23 are in engagement. The clock movement I has been stated to be an eight-day movement, but, of course, this may be any spring driven movement and may have its driving spring kept wound through suitable gearing from the secondary motor I4 instead of being manually wound by key 89 as shown in the drawings.

Referring to Fig. 3, the manual resetting apparatus comprises a control clock C which is mounted in the same location a the resetting switch R. In case of a current interruption on this system, both the control clock C and the secondary clocks will of course stop. When cur rent is resumed all clocks will operate at normal speed but will, of course, be slow by the amount of the current interruption. It is then necessary for the operator to close key R, connecting one ide of the supply line to conductor I02 which extends to the magnets 19 in the secondary clocks. These magnets then energize and change the speed ratio of the gearing so that the secondary clocks and the control clock are driven at three times normal speed. The operator maintains the key R closed until the control clock has been reset to correct time. All secondary clocks on the system will be in synchronism with the control clock and will also be reset to correct time.

Although only one embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that numerous changes and modifications can be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Having described the invention, what is claimed a new and is desired to have protected by Letters Patent is:

1. In an automatic resetting control apparatus for a synchronous motor time system, a source of alternating current, a spring driven clock movement, means normally holding said clock movement inoperative and released upon failure of current flow from said source to start said clock movement, means effective upon resumption of current flow for holding said first means in released position, a normally inoperative synchronous motor started upon resumption of current flow following an interruption therein, and means jointly controlled by said motor and said clock movement for rendering said motor inoperative and for rendering said first means effective to stop said time movement.

2. In an automatic resetting control apparatus for an electric time system, a source of current, a time movement, means normally holding said time movement inoperative and released to start said movement upon cessation of current flow from said source, electrically operated control means cooperating with said time move ment for controlling the resetting of the time system, a circuit to said control means prepared by said time movement, means effective upon resumption of current flow from said source for holdin said first means in released position, and means jointly controlled by said time movement and said control means for again rendering said first means eifective to stop said time movement and for opening the circuit to said control means.

3. In an automatic resetting control apparatus for an electric time system, a source of current, a normally inoperative, mechanically driven time movement, a normally inoperative electrical tim ing device, a normally energized magnet, means controlled by said magnet when released by an interruption in current flow from said source for starting said time movement, means controlled by said time movement for preparing a circuit to said electric timing device, and means jointly controlled by said time movement and said timing device for resetting the time system to correct time when current flow is resumed following the interruption, said mean opening the circuit to said timing device and causing said magnet to again energize to stop said time movement.

4. In an automatic resetting control apparatus for an electric time system, a source of current, a mechanically driven time movement, a first cam means controlled thereby, an electric driving means, a second cam means driven thereby at a speed several times greater than the speed at which said first cam means is driven by said time movement, said two cam means being normally in predetermined relative positions, means effective upon failure of current flow from said source for starting said time movement, contact means jointly controlled by said first and said second cam means for preparing the circuit to said electric driving means to start same when current flow is resumed following the interruption, and means including said contact means for stopping both said time movement and said electric driving means when said first and said second cam means again reach said predetermined relative positions.

5. In a time system, a master control apparatus and a secondary apparatus connected by a control circuit, a source of current, time elements in said secondary apparatus, electric driving means for normally driving said time elements to correctly manifest the passing of time, means for changing the speed ratio between said driving means and said time elements, a normally inoperative mechanically driven time movement in said master apparatus, means for starting said time movement upon failure of current flow from said source, a normally inoperative electric driving means in said master apparatus automatically operative when current flow is resumed following the interruption, means jointly controlled by said time movement and said electric drivin means in said master apparatus for operating said speed ratio changing means in said secondary apparatus to drive said time elements at increased speed, and. means effective when said time elements again indicate correct time for releasing the speed ratio changing means in said secondary apparatus and for stopping said time movement and said electric driving means in said master apparatus.

6. In a time system, a plurality of secondary devices each equipped with a, synchronous motor for driving the time elements thereof, master apparatus connected to said secondary devices by a control circuit, a source of alternating current connected to said master apparatus, a spring driven clock movement in said master apparatus, means controlled by current from said source for normally holding said movement inoperative and for starting same upon cessation of current flow from said source, means controlled from said master apparatus and effective upon resumption of current flow follow ing an interruption therein for causing the synchronous motor in. each secondary device to drive the associated time elements at increased speed, and means operative only when said secondary devices have been reset to correct time for stopping said clock movement and restoring said secondary devices to normal speed operation.

GEORGE C. ENGEL. ADOLPH AMEND, JR. 

